#4 Cristian Javier (2022 version)
Cristian Javier comes with a qualifier--that the Critian Javier of old returns. If 2023 Javier is in the Astros rotation, there is just no way to call it a "dream." But if the Astros get the untouchable Javier back, he legitimately can be a #1.
When Cristian Javier is locating his fastball up with the correct arm angle, he's impossible to touch. But when his arm angle misses, his slider doesn't play nearly as well. While his fastball still had a run value of 12 in 2023 (down from 18 in 2022), his slider run value was -2 after being an 8 in 2022.
His 2023 was a tale of two seasons. In March/April, May and September/October, Javier threw 94.1 innings, posting a 3.34 ERA and striking out 107 batters. He looked like the Javier of 2022.
But from June to August, Javier looked like a AA spot starter. He allowed 47 earned runs in only 67.2 innings of work. He wasn't missing bats and gave up home runs galore.
The postseason was more of the same for Javier. He dominated the Twins in Game 3 of the ALDS and mowed down Texas in Game 3 of the ALCS, but got absolutely rocked in game 7 of the ALCS, recording only one out and giving up four runs.
If Houston can get 2022 Cristian Javier back, or even if his 2.54 ERA doesn't return, just an ERA in the low to mid 3's, they're in incredible shape. And as part of a six-man rotation, it's entirely possible Javier gets the rest he needs and does just that.